Old information

Because of the frustration US export regulations caused, I wrote 1989 my own DES library, AloDES, in C.

It is a quite fast portable DES library. The package also has an efficient bignum library. Simple programs to use libraries are also included.

If you need a bignum DLL for Windows environment, you can get GNU Copylefted version here. It is modified for use in Windows ssh, which is a commercial product of Data Fellows.

Addendum of 2000-10-15

This is quite outdated software package. If you need modern, supported and royalty free crypto package, I warmly recommend software found at U.S National Institute of Standards and Technology has announced the nation's proposed new Advanced Encryption Standard. This finally makes DES officially outdated as an algorithm. OpenSSL will probably have an AES implementation but in the meantime other good algorithms in OpenSSL can be used.